Devices for the treatment of biological tissue

ABSTRACT

An apparatus for treating a subcutaneous fat region is provided. The apparatus includes a housing that has a skin contacting portion defining a chamber. The apparatus also includes a first spaced region in the housing through which a coolant passes and a second spaced region in the housing that is at least partially evacuated of air. The apparatus further includes a source of electromagnetic radiation, a source of vacuum in fluid communication with the chamber, and a source for the coolant.

FIELD OF THE INVENTION

The invention relates generally to devices for treating biologicaltissue, and more particularly, to treatment devices with integratedelectromagnetic radiation, cooling and vacuum functions.

BACKGROUND OF THE INVENTION

Lasers, lamps, and other sources of electromagnetic radiation areutilized for various dermatological treatments including, for example,treatment of subcutaneous fat, treatment of sweat glands and removal ofunwanted hair. For many of these applications, electromagnetic radiationis to be delivered at a selected depth in biological tissue.

However, when treating a large area of tissue simultaneously usingelectromagnetic radiation, it becomes difficult to provide substantiallyuniform radiation over the entire area so that sufficient radiation isapplied to all portions of the area to achieve the desired treatment,while no portion of the area has so much radiation exposure as toexperience thermal damage. Therefore, energy-emitting devices are neededto permit optimized utilization and delivery of electromagneticradiation to a target treatment area.

SUMMARY OF THE INVENTION

The invention, in various embodiments, provides energy-emitting devicesfor treating biological tissue. The devices provide optimized deliveryof electromagnetic radiation to simultaneously treat a relatively largearea of the biological tissue. The devices also offer integrated heatmanagement capabilities, providing cooling for both the energy-emittingsource and surface cooling of the biological tissue being irradiated.Furthermore, the devices can provide vacuum capabilities, which areutilized for pain reduction as well as to increase efficacy and safetyof light-based dermatological treatments.

In one aspect, an apparatus for treating a subcutaneous fat region isprovided. The apparatus includes a housing that has a skin contactingportion defining a chamber, which is defined by a bottom surface of afirst transparent optic recessed in the chamber and a rim extending fromthe perimeter of the first transparent optic toward the skin contactingportion. The apparatus also includes a second transparent optic thatincludes a bottom surface spaced from a top surface of the firsttransparent optic. The second transparent optic is disposed in thehousing. The first transparent optic and the second transparent opticdefine a first spaced region through which a coolant passes. Theapparatus also includes a third transparent optic that includes a bottomsurface spaced from a top surface of the second transparent optic. Thethird transparent optic is disposed in the housing. The secondtransparent optic and the third transparent optic define a second spacedregion at least partially evacuated of air. The apparatus furtherincludes a source of electromagnetic radiation disposed in the housingrelative to a top surface of the third transparent optic. In addition,the apparatus includes a source of vacuum in fluid communication withthe chamber. The source of vacuum is capable of removing air from insidethe chamber so that a surface of skin overlying the subcutaneous fatregion is drawn into contact with the bottom surface of the firsttransparent optic. The apparatus further includes a source for thecoolant. The coolant flows through the first spaced region so thatthermal energy is removed through the first transparent optic from anepidermal region and at least a portion of a dermal region overlying thesubcutaneous fat region.

In another aspect, an apparatus for treating a subcutaneous fat regionis provided. The apparatus includes a plurality of diode lasers spacedin a plurality of rows and columns and disposed in a housing to providedelivery of a substantially even distribution of electromagneticradiation to a surface of skin overlying the subcutaneous fat region.The apparatus also includes a cooling device disposed in the housingrelative to a bottom surface of the plurality of diode lasers formodulating a temperature of the surface of skin. The cooling deviceincludes a first, second and third transparent optics through which theelectromagnetic radiation is delivered to the surface of skin. Theapparatus additionally includes a cooling manifold disposed in thehousing relative to a top surface of the plurality of diode lasers. Thecooling manifold is adapted to conduct liquid therethrough to cool theplurality of diode lasers. The apparatus further includes a distancegauge disposed in the housing between the plurality of laser diodes andthe surface of skin. A height of the distance gauge, a distance betweensuccessive rows of the diodes, a distance between successive columns ofthe diodes or a combination thereof is adjustable to provide thesubstantially even distribution of the electromagnetic radiation.

In another aspect, an apparatus for treating a subcutaneous fat regionis provided. The apparatus includes a source of vacuum in fluidcommunication with a chamber in a housing. The chamber is defined by abottom surface of a cooling device recessed in the chamber and a rimextending from the perimeter of the bottom surface toward a skincontacting portion. The apparatus also includes a source ofelectromagnetic radiation disposed in the housing relative to a topsurface of the cooling device for delivering, during at least a portionof a treatment period, an even distribution of the electromagneticradiation simultaneously to a surface of skin overlying the subcutaneousfat region. The surface of skin has an area of at least 10 cm². Inaddition, the vacuum is adapted to remove air from inside the chamberduring at least a portion of the treatment period so that the surface ofskin is uniformly drawn into contact with the bottom surface of thecooling device without causing petechiae to the surface of skin.

In another aspect, an apparatus is provided for modulating a temperatureof skin tissue overlying a subcutaneous fat region while treating thesubcutaneous fat region using a source of electromagnetic radiation. Theapparatus includes a first transparent optic disposed in a housing. Thefirst transparent optic is adjacent to a skin contacting portion of thehousing. The apparatus also includes a second transparent optic disposedin the housing. The second transparent optic includes a bottom surfacespaced from a top surface of the first transparent optic. The firsttransparent optic and the second transparent optic define a first spacedregion through which a coolant passes to remove thermal energy from anepidermal region of the skin tissue, a dermal region of the skin tissue,or the subcutaneous fat region or a combination thereof. The apparatusadditionally includes a third transparent optic disposed in the housing.The third transparent optic includes a bottom surface spaced from a topsurface of the second transparent optic. The second transparent opticand the third transparent optic define a second spaced region at leastpartially evacuated of air.

In some embodiments, the apparatus further includes a chamber in thehousing defined by a bottom surface of the first transparent opticrecessed in the chamber and a rim extending from the perimeter of thefirst transparent optic toward the skin contacting portion. In someembodiments, the source of electromagnetic radiation is disposed in thehousing relative to a top surface of the third transparent optic. Insome embodiments, the apparatus further includes a source of vacuum influid communication with the chamber. The source of vacuum is adapted toremove air from inside the chamber so that a surface of skin overlyingthe subcutaneous fat region is drawn in contact with the bottom surfaceof the first transparent optic.

In other examples, any of the aspects above can include one or more ofthe following features. At least one of the transparent optics can besapphire. In some embodiments, the first transparent optic is sapphire.The second spaced region of the apparatus can house a thermallyinsulative gas. The skin contacting portion can flatten the surface ofskin or compress the surface of skin, or a combination thereof, whilethe subcutaneous fat region is being treated.

In some embodiments, the apparatus further includes a controller inelectrical communication with the source of electromagnetic radiationand the source of vacuum. The controller receives a signal when athreshold value of pressure is reached. The controller then triggers thesource of electromagnetic radiation to deliver the electromagneticradiation to the subcutaneous fat region.

In some embodiments, the source of electromagnetic radiation includes aplurality of diode lasers. The plurality of laser diodes can be spacedin a plurality of rows and columns to provide delivery of asubstantially even distribution of the electromagnetic radiation to thesurface of skin. Adjacent columns can be spaced by about 5 mm andadjacent rows can be spaced by about 20 mm. The plurality of laserdiodes can include a diode laser bar having 10 diode lasers along eachrow and 5 diodes along each column. Each laser diode can have about a12-degree divergence along a row direction, which is the axisperpendicular to the p-n junction of the laser diode, and about a45-degree divergence along a column direction, which is the axisparallel to the p-n junction. In some embodiments, the power emitted byeach laser diode is about 3 W. In some embodiments, the fluence rate ofeach laser diode is about 2 W/cm², after accounting for transmissionlosses through the optics and coolant fluid.

In some embodiments, the apparatus can supply a substantially sameamount of current to each of the plurality of laser diodes. In someembodiments, the apparatus can supply different amounts of current to atleast two of the plurality of laser diodes to compensate for variationsin efficiency among the laser diodes.

In some embodiments, the apparatus can further include a distance gaugebetween the plurality of the laser diodes and the skin contactingportion. A height of the distance gauge, a distance between successiverows of the diodes, a distance between successive columns of the diodes,or a combination thereof can be adjusted to provide the substantiallyeven distribution of the electromagnetic radiation.

The source of electromagnetic radiation can provide radiation having awavelength of about 1,200 nm to about 1,230 nm and a power density ofless than or equal to about 2.3 W/cm². The apparatus can deliver theelectromagnetic radiation simultaneously to the surface of skin havingan area of at least 50 cm². The apparatus can deliver theelectromagnetic radiation for at least 300 seconds.

The apparatus can further include a cooling manifold in communicationwith the source of electromagnetic radiation. The cooling manifold isconfigured to conduct liquid therethrough to cool the source ofelectromagnetic radiation. In some embodiments, the coolant in the firstspaced region additionally removes thermal energy from at least aportion of the subcutaneous fat region, such as the upper subcutaneousfat region, and from the skin overlaying the portion of subcutaneous fatregion.

Other aspects and advantages of the invention will become apparent fromthe following detailed description, taken in conjunction with theaccompanying drawings, illustrating the principles of the invention byway of example only.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages of the invention described above, together with furtheradvantages, may be better understood by referring to the followingdescription taken in conjunction with the accompanying drawings. Thedrawings are not necessarily to scale, emphasis instead generally beingplaced upon illustrating the principles of the invention.

FIG. 1 shows an embodiment of a system for treating biological tissue.

FIG. 2 shows another embodiment of a system for treating biologicaltissue.

FIG. 3 shows an exemplary cooling portion of an applicator.

FIG. 4 shows a side view of an exemplary applicator.

FIG. 5 shows a top view of an exemplary applicator.

FIG. 6 shows an exemplary laser array of an applicator.

FIGS. 7a and 7b show various views of an exemplary laser power densitydistribution pattern produced using an applicator.

FIGS. 8a and 8b show exemplary laser power density distribution measuredat a skin surface along the x-axis and the y-axis, respectively.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows an embodiment of a system 100 for treating biologicaltissue. The system 100 can be used to non-invasively deliver radiationto a target region. For example, the radiation can be delivered throughan external surface of skin over the target region. The system 100includes an energy source 102 and a delivery system 104. In oneembodiment, radiation provided by the energy source 102 is directed viathe delivery system 104 to a target region. In the illustratedembodiment, the delivery system 104 includes an umbilical cable 106having a circular cross-section and an applicator 108. The umbilicalcable 108 can house at least one of an electrical power line, a vacuumline and a coolant line connected to the applicator 108. The applicator108 can include laser diodes and/or an optical system (e.g., an optic orsystem of optics) to direct the radiation to the target region. Theapplicator 108 can be a handheld device, such as a handpiece, which canbe held or manipulated by a user to irradiate the target region. Thedelivery system 104 can be positioned in contact with a skin surface,adjacent a skin surface, proximate a skin surface, spaced from a skinsurface, or a combination thereof. In the embodiment shown, the deliverysystem 104 includes a spacer 110 to space the delivery system 104 fromthe skin surface. A spacer 110 is not required however. In oneembodiment, the spacer 110 can be a distance gauge, which can aid apractitioner with placement of the delivery system 104.

To minimize unwanted thermal injury to tissue not targeted (e.g., anexposed surface of the target region and/or the epidermal layer), thedelivery system 104 can include a cooling system (not shown) for coolingbefore, during or after delivery of radiation, or a combination thereof.Cooling can include contact conduction cooling, evaporative spraycooling (using a solid, liquid, or gas), convective air flow cooling, ora combination thereof. If cooling is used, it can cool the mostsuperficial layers of tissue overlying the intended treatment area.Cooling can facilitate leaving the overlying skin intact during lasertreatment.

FIG. 2 shows another embodiment of a system 120 for treating biologicaltissue. The system 120 is configured to form a pattern of treatmentzones in skin. System 120 can include a base unit 122 coupled to anumbilicus 124, which is connected to a delivery module 104. The baseunit 122 includes a power source 128 that supplies power to varioussystem components, including an energy source 126 housed in the deliverymodule 104. The base unit 122 also includes a controller 132, which canbe coupled to a user interface and can include a processing unit. Thebase unit 122 can include a cooling system 130 for cooling the skinsurface and the delivery module 104, such as cooling one or more laserdiodes of the delivery module 104. The base unit 122 can also include avacuum system 134.

The system 120 can be used to non-invasively deliver an array ofradiation beams to a target region of the skin. For example, the arrayof radiation beams can be delivered through an external surface of skinover the target region. In one embodiment, a beam of radiation providedby the energy source 126 is directed via the delivery module 104 to atarget region. The umbilicus 124 can act as a conduit for communicatingpower, signal, vacuum, fluid and/or gas between the base unit 122 andthe delivery module 104. The umbilicus 124 can include a fiber todeliver radiation from the base unit 122 to the delivery module 104. Thedelivery module 104 can include an optical system (e.g., an optic or asystem of optics) to convert a beam of radiation into an array ofradiation beams and direct the array to the target region. The deliverymodule 104 can supply electrical power from power source 128 to theenergy source 126. The delivery module 104 can include one or more laserdiodes or light-emitting diodes, or include one or more optical fibersdelivering light from a source such as laser diodes. The optical systemcan include a mask or focusing system to provide radiation havingregions where no treatment radiation is delivered (e.g., to create apattern of undamaged tissue or skin surrounded by damaged tissue orskin). A user can hold or manipulate the delivery module 104 toirradiate the target region. The delivery module 104 can be positionedin contact with a skin surface, adjacent a skin surface, proximate askin surface, spaced from a skin surface, or a combination thereof. Insome embodiments, an array of radiation beams can be formed from asingle beam of radiation by a system of optics.

To minimize unwanted thermal injury to tissue not targeted (e.g., anexposed surface of the target region and/or the epidermal layer), thedelivery module 104 can include a cooling module for cooling before,during or after delivery of radiation, or a combination thereof. Coolingcan include contact conduction cooling, evaporative spray cooling,convective air flow cooling, or a combination of the aforementioned.

In various embodiments, the energy source 102 of the system 100 or theenergy source 126 of the system 120 can be an incoherent light source ora coherent light source (e.g., a laser). The energy sources 102, 126 canbe broadband or monochromatic. The radiation can be a pulsed beam, ascanned beam, or a gated continuous wave (CW) beam. The laser can be adiode laser, a solid state laser, a fiber laser, or the like. Anincoherent source can be a light emitting diode (LED), a flashlamp(e.g., an argon or xenon lamp), an incandescent lamp (e.g., a halogenlamp), a fluorescent light source, or an intense pulsed light system.The incoherent source can include appropriate filters to block unwantedelectromagnetic radiation. The energy sources 102, 126 can be housed inthe system console or in an applicator, such as handpiece.

FIG. 3 shows an exemplary cooling portion 140 of an applicator, whichcan be the applicator 108 of the system 100 or the delivery module 104of the system 120. The cooling portion 140 can include a coolant chamber144 formed by two optical windows 148, 152 and sidewalls 154. Cooledrefrigerant is passed through the flow chamber 144, cooling the window148 that is in contact with a surface of skin 156, thereby cooling theskin surface 156.

One disadvantage of a one-chamber design is that it also cools theexterior of the window 152, which can lead to water droplets or frostforming on the exterior of the window 152 due to condensation ofatmospheric water vapor. Condensation is generated depending on thetemperature of the refrigerant and relative humidity. To avoidcondensation, the cooling portion 140 includes a third optical window160 to form a second chamber 164 defined by the windows 152, 160 and thesidewalls 154. The second chamber 164 can be filled with either athermally insulating gas, such as argon, krypton, or dry nitrogen. Insome embodiments, the second chamber 164 is fully or partiallyevacuated.

The first optical window 148 can be made from a substance that has goodthermal conductivity such as crystalline sapphire. Each of the windows148, 152 and 160 can be a sapphire or glass window. In an exemplaryconfigure, the first optical window 148 is made of sapphire while thesecond window 152 and the third window 160 are made of glass or othermaterial(s) of low thermal conductivity to minimize condensation. All ofthe windows 148, 152 and 160 as well as the chilled coolant fluid in thecoolant chamber 144 can be transparent to the intended wavelength(s) ofthe applied laser radiation 168.

In some embodiments, the coolant chamber 144 can allow a flow of chilledcoolant. The coolant can be chilled water, a fluorocarbon type coolingfluid such as chilled Fluorinert, a cryogenic fluid, or the like. Thecoolant can be transparent to the radiation 168 used during treatment.The coolant chamber 144 can allow sufficient flow of the coolant toavoid a significant increase in the water temperature in the chamber144. The coolant chamber 144 can include one or more plenums or ports toavoid eddies within the chamber 144. For some laser wavelengths wherethe coolant can absorb the laser radiation, the coolant chamber 144 canbe made sufficiently thin to avoid excessive absorption of the laserenergy by the fluid in the chamber 144. Minimizing the thickness of thecoolant chamber 144 can also facilitate an even flow of the coolantthrough the chamber 144 and decreases the required cross-sectional areaof the coolant supply line and coolant return line. In some example, thecoolant chamber 144 is about 0.5 mm thick.

The second chamber 164 can be purged, filled with argon, and sealed.Alternatively, the second chamber 164 can be evacuated and filled withkrypton or some other thermally insulating gas.

The upper and lower surfaces of the third optical window 160 can becoated with an antireflective film chosen to minimize reflection at thelaser wavelength(s). The upper surface of the second optical window 152,which is the surface facing the second chamber 164, can be coated withan antireflective film chosen to minimize reflection at the laserwavelength(s).

FIG. 4 shows a side view of an exemplary applicator 170, which can bethe applicator 108 of the system 100 or the delivery module 104 of thesystem 120. The applicator 170 can incorporate the cooling portion 140as described above with reference to FIG. 3, a source of electromagneticradiation 172 and a vacuum chamber 174.

The cooling portion 140 includes the first, second and third opticalwindows 148, 152, 160. The cooling portion 140 also includes the coolantchamber 144, defined by the windows 148, 152 and the sidewalls (notshown), to allow a flow of chilled coolant through the chamber 144. Thecooling portion 140 further includes the second chamber 164 that isfully or partially evacuated and filled with an insulating gas, such asargon. Surfaces defining the second chamber 164 include the sidewalls154, the lower surface of the third window 160 facing the second chamber164 and the upper surface of the second window 152 facing the secondchamber 164. In some embodiments, the upper and lower surfaces of thethird window 160 and the upper surface of the second window 152 arecoated with an antireflective film to minimize reflection of the lasergenerated by the electromagnetic radiation source 172. In someembodiments, the inner surfaces of the sidewalls 154 facing the secondchamber 164 are coated with a reflective film to maximize reflection ofthe laser generated by the electromagnetic radiation source 172 andsmooth the laser distribution at the edge of the treatment area. In someembodiments, a bottom surface of the first optical window 148 is adaptedto contact a skin surface during treatment and is thus suitablyconfigured to flatten and/or compress the skin surface.

The vacuum chamber 174 of the applicator 170 is defined by the bottomsurface of the first optical window 148 that is recessed in the chamber174 and a rim 182 extending from the perimeter of the bottom surface ofthe first optical window 148 to make contact with the skin.Specifically, the vacuum chamber 174 is exposed to a surface of skinoverlying a target treatment region such that when air is removed frominside the chamber 174, the skin surface is drawn into contact with thebottom surface of the first optical window 148. In some embodiments, asource of vacuum (not shown) is in fluid communication with the vacuumchamber 174 to remove air from the chamber 174. In some embodiments, therim 182 includes a skin-contacting portion that, when placed on the skinsurface, spatially confines the treatment area to the enclosed tissue.

In various embodiments, vacuum applied to the vacuum chamber 174 ensuresthat the skin surface through which the treatment beam passes is in goodcontact with the cooling window 148 during surface cooling, whichestablishes a safer treatment environment and facilitates painreduction. In addition, vacuum in the vacuum chamber 182 can hold theapplicator 170 in place, thereby providing hand-free treatment. This isparticularly useful when treatment times are long.

In various embodiments, the electromagnetic radiation source 172includes a plurality of lasers 176 for generating sufficientelectromagnetic radiation to be delivered to a target tissue regionthrough the cooling portion 140, the vacuum chamber 174 and the skinsurface overlying the target region. The lasers 176 can be diode lasersor other light-emitting lasers. If the lasers 176 are diode lasers, theycan be made of indium phosphide (InP), indium gallium arsenide phosphide(InGaAsP), or another suitable material.

The lasers 176 can form a laser array 177 with one or more rows andcolumns to deliver a substantially even distribution of theelectromagnetic radiation to the skin overlying the targeted region. Insome embodiments, one or more cooling bars 178 are provided to cool atleast one surface of each of the lasers 176. In addition, theelectromagnetic radiation source 172 includes one or more coolingmanifolds 180 in thermal communication with the laser array 177 toprovide additional cooling.

FIG. 5 shows a top view of the exemplary applicator 170 of FIG. 4. Forthe purpose of illustration, the lasers 176 of the electromagneticsource 172 are arranged in an array 177 of five rows along the y-axis202, with each row having ten lasers spaced along the x-axis 200. Eachrow of ten lasers 176 can be attached to a laser bar 204 along one orboth sides of the bar 204 and aligned with the x-axis 200. In addition,the output emission of the lasers 176 is directed to the lower surfaceof the laser bar 204, which is the surface facing the skin when theapplicator 170 is operated during treatment. As shown, the laser array177 includes five laser bars 204 uniformly spaced along the y-axis 202.In other embodiments, however, there can be more than or fewer than fivelaser bars 204 included in the electromagnetic source 172. There can bemore than or fewer than ten lasers 176 attached to each of the laserbars 204. The number of laser bars 204 and/or the number of lasers 176per bar can be selected based on the size and shape of the treatmentregion.

In some embodiments, each laser 176 is mounted on the lower surface ofthe respective laser bars 204 using one or more 5 mm×5 mm ceramic mounts206, which can have high thermal conductivity and low electricalconductivity. For example, a single, appropriately-sized ceramic mount206 can be used to hold lasers 176 to an entire laser bar 204, such asten lasers 176 per laser bar 204. In some embodiments, one or more 3mm×5 mm ceramic mounts 206 are used to attach more lasers 176 to eachlaser bar 204. In some embodiments, each ceramic mount 206 is about 1 mmor less in thickness. Thinner mounts 206 can optimize heat conductionfrom the lasers 176 to the treatment area. The ceramic mounts 206 can befabricated from materials with high thermal conductivity, such asaluminum nitride or beryllium oxide. In some embodiments, a ceramicmount 206 has a thermal conductivity greater than about 150 W/m-K and adielectric constant greater than about 5.

In some embodiments, a cooling channel (not shown) is disposed withineach laser bar 204. The cooling channel can substantially span thelength of a laser bar 204 to provide uniform cooling to the lasers 176coupled to each bar 204. Two cooling manifolds 180 can be coupled to theupper surface of the laser bars 204. Each cooling manifold 180 cansimultaneously overlap all the laser bars 204 to provide a uniform flowof coolant to the cooling channels in the laser bars 204, therebyuniformly cools the lasers 176. The coolant can be water maintainedbetween about 5 C. and about 25 C. or between 20 C. to about 25 C. Insome embodiments, the coolant flowing through the cooling channels andthe cooling manifolds 180 is from the same source as the coolantprovided to the coolant chamber 144 of the cooling portion 140. In someembodiments, even though the same coolant is provided to the coolantchamber 144, the cooling channel, and the cooling manifolds 180, thecoolant flowing through each of the three components is maintained at adifferent temperature. In some embodiments, different coolants areprovided to the three components.

As shown in FIG. 5, the applicator 170 can also include a distance gauge205 to maintain a distance between the laser array 177 and the skinsurface. In some embodiments, the distance gauge is about 36.7 mm high,capable of maintaining a distance of about 36.7 mm between the laserarray 177 and the skin surface.

FIG. 6 shows an exemplary laser array 177 of the applicator 170. Ay-distance 208 of about 20 mm can be maintained between two successiverows of the lasers 176 in the array 177 and a x-distance 210 of about 5mm can be maintained between two successive columns of the lasers 176.This arrangement 177 can deliver a substantially uniform distribution ofelectromagnetic radiation to a surface area of about 10 cm along they-axis 202 and about 5 cm along the x-axis 200. In some embodiments,every other row in the array 177 is offset from the adjacent rows byhalf of the x-distance 210 along the x-axis 200, such as by about 2.5 mmif the y-distance is about 5 mm.

Each laser 176 can have an elliptical electromagnetic radiationdistribution pattern that is mathematically approximated by atwo-dimensional Gaussian distribution having a fast axis, whichrepresents the axis perpendicular to the p-n junction of the laser, anda slow axis, which represents the axis parallel to the p-n junction ofthe laser. In some embodiments, the lasers 176 are arranged such thattheir fast axis corresponds to the y-axis 202. The angle of divergence(FWHM) for the fast axis of each laser 176 can be greater than 30degrees, such as approximately 37 degrees or 45 degrees. Therefore, ifthe distance gauge 205 of the applicator 170 is 36.7 mm in height (i.e.,the distance between the lasers 176 and the skin surface is about 36.7mm), the FWHM beam diameter of each laser 176 along the y-axis 202 isapproximately 30.4 mm. In some embodiments, the lasers 176 are arrangedsuch that their slow axis corresponds to the x-axis 200. The angle ofdivergence (FWHM) for the slow axis of each laser 176 can beapproximately 12 degrees. Therefore, if the distance gauge 205 is about36.7 mm in height, the FWHM beam diameter of each laser 176 along thex-axis 200 is approximately 7.71 mm. However, because theelectromagnetic radiation generated by the laser array 177 is deliveredto the skin surface through the first, second and third optical windows148, 152, 160 of the cooling portion 140 as well as through the coolantin the coolant chamber 144 and/or the gas in the second chamber 164 ofthe cooling portion 140, the actual x-axis and y-axis diameters of thelasers 176 in the laser array 177 may be slightly different than thegiven approximations.

In general, any one of the x-distance 210, the y-distance 208, and thevertical distance between the lasers 176 and the skin surface, which canbe represented by the height of the distance gauge 205, can be adjustedto achieve a relatively even energy distribution over the treatmentarea, even though each individual laser 176 may have a Gaussian-likebeam. In some embodiments, because the x-distance 210 and the y-distance208 are dependent on the distance between the lasers 176 and the skinsurface, by fixing one of the three values, the other two values can bedetermined to achieve a relatively uniform energy distribution over atreatment area. As an example, the x-distance 210 (denoted as g_(x)) isfirst set to a fixed value, such as about 5 mm, which is about the sameas the thickness of the ceramic mount 206 so that the lasers 176 areabout 5 mm apart along the x-axis 200. In addition, the slow-axisdivergence (denoted as ang_(s)) is a constant value, such as about 12degrees. Then, the distance between the lasers 176 and the skin surface(denoted as d_(z)) can be suitably optimized using Equation 1 below toachieve an overall uniform beam distribution along the x-axis 200:

$\begin{matrix}{d_{z} = {\frac{g_{x}}{2 \times {\tan( \frac{{ang}_{s}}{2} )}} \times \{ {{Overlap}\mspace{14mu}{Factor}} \}}} & ( {{Equation}\mspace{14mu} 1} )\end{matrix}$The overlap factor of Equation 1 can be a value selected between 1 and10, where 1 minimizes the number of lasers used to cover a fixed area.However, the fewer the number of lasers used, the more susceptible beamuniformity is to diode energy variations, including to dropped (e.g.,burned-out) diodes. In contrast, a larger overlap factor corresponds tothe use of more diodes to illuminate the same fixed area. However, theresulting beam uniformity is less sensitive to energy variations anddropped diodes. In addition, because the height of the applicator 170 islarger than and dependent on the distance d_(z) between the lasers 176and the skin surface, the height of the applicator 170 can be reduced byreducing the distance g_(x) between the diodes placed along the x-axis200, as shown in Equation 1. Equation 1 also shows that the value of theoverlap factor affects the height of the applicator 170 as well.

After optimizing the distance d_(z) between the lasers 176 and the skinsurface, the placement of diodes along the y-axis 202, as represented bythe y-distance 208 (denoted as g_(y)), can be optimized to achieve anoverall uniform beam distribution along the y-axis 202. Specifically,using d_(z) computed from Equation 1 and the fast-axis divergence value(denoted as ang_(f)), which can be about 45 degrees, the distance g_(y)can be suitably optimized using Equation 2 below:

$\begin{matrix}{g_{y} = {2d_{z} \times {{\tan( \frac{{ang}_{f}}{2} )}/\{ {{Overlap}\mspace{14mu}{Factor}} \}}}} & ( {{Equation}\mspace{14mu} 2} )\end{matrix}$The overlap factor of Equation 2 can be selected to be the same as ordifferent from the overlap factor of Equation 1.

In various embodiments, the number of lasers 176 used, including thenumber of lasers 176 per row and/or the number of lasers per column ofthe laser array 177, is determined based on the size and/or shape of thetreatment area. For example, the laser array 177, which includes 50lasers organized in a 5-row-by-10-column formation, can treat arectangular area of 10 cm (along the y-axis 202) by 5 cm (along thex-axis 200) if the y-distance 208 is set to about 20 mm betweensuccessive rows and the x-distance 210 is set to about 5 mm betweensuccessive columns. In some examples, the treatment area can be circularor elliptically, having a diameter between about 1 cm and about 6 cm. Insome examples, the surface of skin can have an area of at least 10 cm²or at least 50 cm².

In various embodiments, the laser array 177 is configured to produce anelectromagnetic radiation wavelength of between about 400 nm to about4000 nm, although longer and shorter wavelengths can be produceddepending on the application. In certain embodiments, the wavelength ofthe electromagnetic radiation is fat selective. For example, the ratioof coefficients of absorption of fat to water is about 0.5 or greater.The wavelength can be about 875 nm to about 950 nm or about 1175 nm toabout 1250 nm. For example, the wavelength can be about 900 nm to about940 nm or about 1200 nm to about 1240 nm. The wavelength can be about1200 nm to about 1230 nm. In some embodiments, the wavelength is about1210 nm. In some embodiments, multiple laser arrays can be used toachieve a desired wavelength. For example, a first laser array producingelectromagnetic radiation of about 1210 nm can be combined with a secondlaser array producing electromagnetic radiation from about 400 nm toabout 10.6 microns, the combination of which can be further coupled toan RF source, or with an ultrasonic source.

In some examples, the wavelength is non-fat selective, e.g., about 950nm to about 1090 nm, about 1100 nm to about 1160 nm, about 1,300 nm toabout 1625 nm or about 1,800 nm to about 2,200 nm.

In some examples, the wavelength is selected to penetrate a surface ofskin and reach the underlying subcutaneous fat region so as to causedamage to the fat cells in the subcutaneous fat region.

In various embodiments, the power and/or power density of theelectromagnetic radiation generated by the laser array 177 is adjustableby changing the current supplied to the individual lasers 176. For thelaser array 177 shown in FIG. 6, if each laser 177 emits a power ofabout 2 W, such as about 2.4 W, the total power for the entire 50-laserarray 177 is about 120 W. Because the area covered by the array 177 isabout 50 cm² (5 cm×10 cm) if the x-distance 210 is about 5 mm and they-distance 208 is about 20 mm, the average power density provided by thelaser array 177 is about 2 W/cm² after accounting for transmissionlosses through the cooling chamber. In general, the laser powerdelivered to a treatment area can be about 25 W to about 125 W, althoughhigher or lower power can be generated depending on the application. Insome embodiments, the laser power can be about 90 W to about 110 W. Insome embodiments, power density of about 0.5 W/cm² to about 2.5 W/cm² isdelivered to the skin surface.

FIG. 7a shows a profile view of an exemplary laser power densitydistribution pattern produced using the laser array 177 of theapplicator 170. Specifically, to produce the distribution pattern shownin FIG. 7a , the laser array 177 includes five laser bars 204 spacedalong the y-axis 202 with each bar 204 including ten lasers 176 spacedalong the x-axis 200. The y-distance 208 between successive rows of thelasers 176 is about 20 mm and the x-distance 210 between successivecolumns of the lasers 176 is about 5 mm.

The laser array 177 is arranged on top of the cooling portion 140 of theapplicator 170 such that a vertical distance 212 between the top of thelaser array 177 and the upper surface of the third optical window 160 ofthe cooling portion 140 is about 10 mm. The third optical window 160 canbe about 3 mm thick. The second chamber 164 of the cooling portion 140,which is bounded above and below by the third optical window 160 and thesecond optical window 152, respectively, can be about 18.2 mm inthickness 214. The second optical window 152 can be about 3 mm thick.The cooling portion 140 also includes the coolant chamber 144 that isbounded above and below by the second optical window 152 and the firstoptical window 148, respective. The thickness 216 of the coolant chamber144 can be about 0.5 mm. The first optical window 148 can be about 2 mmthick. Overall, a distance of about 36.7 mm can be maintained betweenthe top of the laser bars 204 and the bottom surface of the firstoptical window 148. In some embodiments, a distance gauge (not shown)can be used to maintain this distance. In some embodiments, one or moremirrors 218 or other reflective surfaces can be suitably positionedalong the boundary of a treatment area to define the treatment area andreflect the laser beams so as to smooth the laser distribution at theboundary.

FIG. 7b shows a top view of a laser power density distribution patternmeasured at the skin surface when operating the applicator 170. Thetreatment surface is about 10 cm along the y-axis 202 and 5 cm along thex-axis 200. The distribution pattern shows a relatively homogenous powerdensity distribution with a peak irradiance of about 0.0229 W/cm². Inaddition, the total power measured at the skin surface is about 0.99 W.

FIGS. 8a and 8b show the laser power density distribution measured atthe skin surface along the y-axis 202 and the x-axis 200, respectively.As shown in FIG. 8a , the power density distribution 252 extends nearlyuniformly along a length of the treatment area (about 10 cm), which isparallel to the y-axis 202. Specifically, the power density distribution252 only fluctuates slightly around 0.02 W/cm². Similarly, as shown inFIG. 8b , the power density distribution 250 extends nearly uniformlyalong a width of the treatment area (about 5 cm), which is parallel tothe x-axis 200. As shown, the power density distribution 250 onlyfluctuates slightly around 0.02 W/cm².

In some examples, substantially the same amount of current is suppliedto each of the laser 176 in the laser array 177. In some examples, thecurrent supplied to one or more of the lasers 176 vary to compensate forvariation in the efficiency among the lasers 176. Due to the partialoverlap of Gaussian beams produced by the individual lasers 176, up toabout 20% variations in power among the lasers 176 may be acceptable,provided that the lasers 176 are randomly distributed and not clusteredtogether based on power, such that lower (or higher) powered lasers areadjacent to each other.

In various embodiments, the radiation can have exposure duration betweenabout 3 s and about 1800 s, although longer and shorter exposuredurations can be used depending on the application. In some embodiments,the radiation can have exposure duration of at least 300 seconds, suchas about 300 seconds to about 600 seconds. In some embodiments, a longerexposure time permits radiation to treat at a greater depth into thesubcutaneous fat region in comparison to radiation having a shorterexposure time, providing that all other parameters are the same. Incertain examples, if the power intensity of the applied radiation issharply increased and then lowered during several time intervals, thetreatment duration is less than 300 seconds, such as about 140 secondsto about 300 seconds. The treatment time can be even shorter if thepower intensity is increased slightly after the lowering period.

In various embodiments, power density and treatment duration can beselected to treat a subcutaneous fat region of a subject. For example,an average power density of the electromagnetic radiation generated bythe array 177 of the applicator 170 is between about 0.5 W/cm² to about5 W/cm² and the electromagnetic radiation can be delivered to the skinsurface to treat the subcutaneous fat region for about 40 seconds orlonger, such as about 40 seconds to about 600 seconds. In someembodiments, the average power density is less than or equal to about 2W/cm², such as about 0.5 W/cm² to about 2 W/cm². In some embodiments,the radiation is delivered to the subcutaneous fat region for at leastabout 300 seconds, such as about 300 seconds to about 600 seconds. Thepeak power density of the applied radiation can exceed 2 W/cm², as longas the average power density over a treatment period is less than orequal to about 2 W/cm². In some embodiments, the average power densityof the electromagnetic radiation delivered is less than or equal toabout 2.3 W/cm². In some embodiments, multiple pulses of radiation canbe delivered to the subcutaneous fat region and the sum of the pulsedurations reaches the desired treatment duration.

In some examples, to treat the subcutaneous fat region, the region canbe heated to a temperature of between about 47° C. and about 80° C.,although higher and lower temperatures can be used depending on theapplication. In one embodiment, the temperature is between about 50° C.and about 55° C. In one embodiment, the temperature is about 50° C.

In various embodiments, the radiation delivered to the treatment areausing the applicator 170 can have a fluence of about 50 J/cm² to about1500 J/cm², although larger or smaller fluence can be used depending onthe application.

In various embodiments, the parameters of the radiation can be selectedto deliver the electromagnetic radiation to a predetermined depth. Insome embodiments, the radiation can be delivered to the target regionabout 0.005 mm to about 10 mm below an exposed surface of the skin,although shallower or deeper depths can be selected depending on theapplication. In some embodiments, the depth is about 1 mm to about 3.5mm. In some embodiments, the depth is greater than or equal to 3 mmbelow the surface of skin, where the subcutaneous fat region resides.

In various embodiments, an optical system is used to deliver radiationto a large area beam or as a pattern of beamlets (e.g., a plurality ofmicrobeams having a spotsize of about 0.1-5 mm) to form a pattern ofthermal injury within the biological tissue.

In various embodiments, one or more sensors can be positioned relativeto a target region of skin. For example, a sensor can be positioned incontact with, spaced from, proximate to, or adjacent to the skin target.A sensor can determine a temperature on a surface of the target region,in the target region, or remote from the target region. One or moresensors can also be positioned at various locations in the applicator170 to monitor for example, the temperature of the coolant flowingthrough the coolant chamber 144, the amount of vacuum applied in thevacuum chamber 174, and/or the average laser power in the laser portion174 of the applicator 170. The sensor can be a thermistor, an array ofthermistors, a thermopile, a thermocouple, a thermometer, a resistancethermometer, and a thermal-imaging based sensor, a thermographic camera,an infrared camera or any combination thereof.

In various embodiments, the applicator 170 can include rollers tomassage the skin. For example, skin in the target region or adjacent tothe target region can be massaged and/or vibrated before, during, and/orafter irradiation of the target region of skin. The massage can be amechanical massage or can be manual massage. In one embodiment, theapplicator 170 can provide an additional massage effect by using vacuum,such as the vacuum generated by the vacuum chamber 174, to pull thetissue into the device 170. Massaging the target region of skin canfacilitate removal of the treated fatty tissue from the target region.For example, massaging can facilitate draining of the treated fattytissue from the treated region. Vibrating and/or massaging the skin inthe target region or adjacent to the target region during irradiationcan also reduce or alleviate treatment pain and allow treatment usinghigher power densities.

In various embodiments, a controller is used to automate the treatmentprocess. The controller is in electrical communication with the laserportion 172, the cooling portion 174 and/or the vacuum chamber 174 ofthe applicator 170. For example, the controller can automaticallyinitiate a radiation exposure sequence after detecting that the skin hasestablished full contact with the first optical window 148 of theapplicator 170, or after detecting that sufficient vacuum is applied tothe skin if vacuum is used in the vacuum chamber 174 to draw the skininto contact with the first optical window 148. The controller candynamically select the power density and exposure duration fordelivering electromagnetic radiation to a treatment area, such as to asubcutaneous fat region. If different power densities are used fordifferent time intervals during treatment, the controller can alsoautomatically determine the optimal power density and exposure time foreach of the time intervals.

In addition, the power density and exposure duration can be determinedby the controller based on the thickness of the skin. For example, theintensity of light reaching the subcutaneous layer decreases withincreasing overlying skin thickness due to increase light scattering andabsorption in skin, so increased power is required to cause sufficientthermal damage in the subcutaneous fat. Therefore, the thickness of theskin can be measured over the area of the body to be treated such thatthe treatment fluence and exposure time can be selected and controlledfor each individual and the body area to be treated. In someembodiments, skin thickness can be measured using ultrasonography atabout 10 to 20 MHz for example.

In operation, the laser sequence generated by the laser array 177 of theapplicator 170 can be triggered by pressing a switch on the applicator170, stepping on a food pedal, or automatically triggered after sensinga sufficient differential vacuum in the vacuum chamber 174, such as whenthe vacuum level exceeds 5 inHg. An exemplary laser sequence includes apre-cool period, followed by a laser-on period and followed by apost-cool period. In certain embodiments, the pre-cool and the post-coolperiods are not necessary if the average laser power density is about 2W/cm².

In various embodiments, the applicator 170 can apply the electromagneticradiation to the skin in a stamping mode or by scanning a light sourcealong a surface of the skin. A computerized pattern generator can beused with the applicator 170 or the applicator 170 can be manuallymanipulated to scan the light source.

Processors suitable for the execution of computer programs for operatingthe applicator 170 include, by way of example, both general and specialpurpose microprocessors, and any one or more processors of any kind ofdigital computer. A processor can receive instructions and data from aread-only memory or a random access memory or both. A processor alsoincludes, or be operatively coupled to receive data from or transferdata to, or both, one or more mass storage devices for storing data,e.g., magnetic, magneto-optical disks, or optical disks. Datatransmission and instructions can also occur over a communicationsnetwork. Information carriers suitable for embodying computer programinstructions and data include all forms of non-volatile memory,including by way of example semiconductor memory devices, e.g., EPROM,EEPROM, and flash memory devices; magnetic disks, e.g., internal harddisks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROMdisks. The processor and the memory can be supplemented by, orincorporated in special purpose logic circuitry.

The treatment radiation generated by the applicator 170 can damage oneor more fat cells so that at least a portion of lipid contained withincan escape or be drained from the treated region. At least a portion ofthe lipid can be carried away from the tissue through biologicalprocesses. In one embodiment, the body's lymphatic system can drain thetreated fatty tissue from the treated region. In an embodiment where afat cell is damaged, the fat cell can be viable after treatment. In oneembodiment, the treatment radiation can destroy one or more fat cells.In one embodiment, a first portion of the fat cells is damaged and asecond portion is destroyed. In one embodiment, a portion of the fatcells can be removed to selectively change the shape of the body region.

In some embodiments, the treatment radiation can be delivered to thetarget region to thermally injure, damage, and/or destroy one or morefat cells. For example, the radiation can be delivered to a targetchromophore in the target region. Suitable target chromophores include,but are not limited to, a fat cell, lipid contained within a fat cell,fatty tissue, a wall of a fat cell, water in a fat cell, and water intissue surrounding a fat cell. The energy absorbed by the chromophorecan be transferred to the fat cell to damage or destroy the fat cell.For example, thermal energy absorbed by dermal tissue can be transferredto the fatty tissue. In one embodiment, the radiation is delivered towater within or in the vicinity of a fat cell in the target region tothermally injure the fat cell.

In various embodiments, treatment radiation can affect one or more fatcells and can cause sufficient thermal injury in the dermal region ofthe skin to elicit a healing response to cause the skin to remodelitself. This can result in more youthful looking skin and an improvementin the appearance of cellulite. In one embodiment, sufficient thermalinjury induces fibrosis of the dermal layer, fibrosis on a subcutaneousfat region, or fibrosis in or proximate to the dermal interface. In oneembodiment, the treatment radiation can partially denature collagenfibers in the target region. Partially denaturing collagen in the dermiscan induce and/or accelerate collagen synthesis by fibroblasts. Forexample, causing selective thermal injury to the dermis can activatefibroblasts, which can deposit increased amounts of extracellular matrixconstituents (e.g., collagen and glycosaminoglycans) that can, at leastpartially, rejuvenate the skin. The thermal injury caused by theradiation can be mild and only sufficient to elicit a healing responseand cause the fibroblasts to produce new collagen. Excessivedenaturation of collagen in the dermis causes prolonged edema, erythema,and potentially scarring. Inducing collagen formation in the targetregion can change and/or improve the appearance of the skin of thetarget region, as well as thicken the skin, tighten the skin, improveskin laxity, and/or reduce discoloration of the skin.

In various embodiments, the treatment radiation can cause a zone ofthermal injury formed at or proximate to the dermal interface. Fattytissue has a specific heat that is lower than that of surrounding tissue(fatty tissue, so as the target region of skin is irradiated, thetemperature of the fatty tissue exceeds the temperature of overlyingand/or surrounding dermal or epidermal tissue. For example, the fattytissue has a volumetric specific heat of about 1.8 J/cm³ K, whereas skinhas a volumetric specific heat of about 4.3 J/cm³ K. In one embodiment,the peak temperature of the tissue can be caused to form at or proximateto the dermal subcutaneous fat interface. For example, a predeterminedwavelength, fluence, pulse duration, and cooling parameters can beselected to position the peak of the zone of thermal injury at orproximate to the dermal subcutaneous fat interface. This can result incollagen being formed at the bottom of the dermis and/or fibrosis at orproximate to the dermal interface. As a result, the dermal interface canbe strengthened against fat herniation. For example, strengthening thedermis can result in long-term improvement of the appearance of the skinsince new fat being formed or untreated fat proximate the dermalinterface can be prevented and/or precluded from crossing the dermalinterface into the dermis. Targeted heating at the dermal subcutaneousfat interface can also affect the base of eccrine and/or apocrine glandsto reduce sweating, thus helpful to subjects with hyperhidrosis orbromhidrosis.

In one embodiment, fatty tissue is heated by absorption of radiation,and heat can be conducted into dermal tissue proximate the fatty tissue.The fatty tissue can be disposed in the dermal tissue and/or can bedisposed proximate to the dermal interface. A portion of the dermaltissue (e.g., collagen) can be partially denatured or can suffer anotherform of thermal injury, and the dermal tissue can be thickened and/or bestrengthened as a result of the resulting healing process. In such anembodiment, a fat-selective wavelength of radiation can be used.

In one embodiment, water in the dermal tissue is heated by absorption ofradiation. The dermal tissue can have disposed therein fatty tissueand/or can be overlying fatty tissue. A portion of the dermal tissue(e.g., collagen) can be partially denatured or can suffer another formof thermal injury, and the dermal tissue can be thickened and/or bestrengthened as a result of the resulting healing process. A portion ofthe heat can be transferred to the fatty tissue, which can be affected.In one embodiment, water in the fatty tissue absorbs radiation directlyand the tissue is affected by heat. In such embodiments, a waterselective wavelength of radiation can be used.

In various embodiments, a treatment can cause minimal cosmeticdisturbance so that a subject can return to normal activity following atreatment. For example, a treatment can be performed without causingdiscernible side effects such as bruising, open wounds, burning,scarring, or swelling. Furthermore, because side effects are minimal, asubject can return to normal activity immediately after a treatment orwithin a matter of hours, if so desired.

In various embodiments, an ultrasound device can be used to measure thedepth or position of the fatty tissue. For example, a high frequencyultrasound device operating at 10 MHz to 20 MHz can be used. Anapplicator of an ultrasound device can be placed proximate to the skinto make a measurement. In one embodiment, the ultrasound device can beplaced in contact with the skin surface. The ultrasound device candeliver ultrasonic energy to measure position of the dermal interface,so that radiation can be directed to the interface.

The time duration of the cooling and of the radiation application can beadjusted so as to maximize the thermal injury to the vicinity of thedermal interface and avoid injury to overlying epidermal and dermaltissue. For example, if the position of the fatty tissue is known, thenparameters of the optical radiation, such as pulse duration and/orfluence, can be optimized for a particular treatment. Coolingparameters, such as cooling time and/or delay between a cooling andirradiation, can also be optimized for a particular treatment.Accordingly, a zone of thermal treatment can be predetermined and/orcontrolled based on parameters selected. For example, the zone ofthermal injury can be positioned in or proximate to the dermalinterface.

While the invention has been particularly shown and described withreference to specific illustrative embodiments, it should be understoodthat various changes in form and detail may be made without departingfrom the spirit and scope of the invention.

The invention claimed is:
 1. A method for treating a subcutaneous fatregion, comprising: delivering a uniform energy distribution ofelectromagnetic radiation to a surface of skin overlying thesubcutaneous fat region using a skin contacting applicator, wherein theelectromagnetic radiation is provided by a plurality of laser diodesspaced in a plurality of rows and columns; wherein the distance betweenthe rows and columns of laser diodes and height of the laser diodes fromthe surface of the skin are chosen to result in uniform energydistribution of the electromagnetic radiation on the skin, and applyinga coolant and removing thermal energy from an epidermal region and atleast a portion of a dermal region of skin overlying the subcutaneousfat region without the coolant being directly exposed to the surface ofthe skin, wherein a height of the laser diodes from the surface of theskin is calculated by the equation:d _(z) =g _(x)/2×tan(ang _(s)/2)×{Overlap Factor} wherein (d_(z))denotes the height of the laser diodes from the surface of the skin,(g_(x)) denotes the distance between the columns and (ang_(s)) denotesthe slow-axis diversion.
 2. The method according to claim 1, furthercomprising drawing the surface of skin overlying the subcutaneous fatregion into contact with a flat window portion of the applicator housingin which the laser diodes are integrated by removing air from inside theportion of the housing.
 3. The method according to claim 2, whereindelivering the electromagnetic radiation to the subcutaneous fat regionwhen a threshold value of pressure is reached.
 4. The method accordingto claim 2, wherein flattening the surface of skin, or compressing thesurface of skin, or a combination thereof, while treating thesubcutaneous fat region.
 5. The method according to claim 2, whereinuniformly drawing the surface of skin into the portion of the housingwithout causing petechiae to the surface of skin.
 6. The methodaccording to claim 1, wherein delivering the electromagnetic radiationto the subcutaneous fat region for at least 300 seconds.
 7. The methodaccording to claim 1, wherein providing electromagnetic radiation havinga wavelength of 1,200 nm to 1,230 nm and a power density of less than orequal to 2.3 W/cm².
 8. The method according to claim 1, whereindelivering the electromagnetic radiation simultaneously to the surfaceof skin having an area of at least 50 square cm.
 9. The method accordingto claim 1, wherein the power emitted by each laser diode is at least 2W.
 10. The method according to claim 1, wherein supplying a same amountof current to each of the plurality of laser diodes.
 11. The methodaccording to claim 1, wherein supplying different amounts of current toat least two of the plurality of laser diodes to compensate forvariations in efficiency among the laser diodes.
 12. The methodaccording to claim 1, wherein also cooling source of the electromagneticradiation.
 13. The method according to claim 1, wherein removing thermalenergy from at least a portion of the subcutaneous fat region andoverlying skin.
 14. The method according to claim 1, wherein distancebetween the rows of the laser diodes is calculated by the equation:g _(y)=2d _(z)×tan(ang _(f)/2)/{Overlap Factor} wherein (g_(y)) denotesdistance between the rows of the laser diodes, (ang_(f)) denotes thefast-axis diversion.